# Goodbye, John H. Conway

Tue 21 April 2020 by Moshe Zadka

John H. Conway passed away ten days ago, and I think it's only now I can write a proper eulogy.

I was first introduced to his work, if not his name, when I was at the end of elementary school. I am sure everyone has heard about the Game of Life, but did you know it had a 1D version? The 1D version is significantly simpler, but has the advantage that on a grid paper, you can just play with yourself manually by putting a generation on each line.

This was 12 year old me's "fidget spinner", how I kept myself calm in classes. Starting with an initial configuration and letting it evolve.

Later on, when I went to college, I got to borrow his amazing book, "On Numbers and Games". Now, I am definitely the sort of person who reads math books for fun, but most of them are not fun. They are dry, poorly written, and make leaps all the time. "ONAG" was the exact opposite. It's a short, delightful book, that tries to get across the thinking, the intuition, the methods, and, yes, the joy.

Fast forward a decade or two, and again I found myself enamored with another one of his inventions: the Look-and-Say sequence. My old interview coding question was getting too popular on the interview-question-sites, and I was getting worried. Writing code for the look-and-say sequence is reasonably straightforward, but does require basic skills: looping while keeping a bunch of state variables.

Then I read about his work on the look-and-say sequence, and was utterly amazed and delighted by it. Atoms and decay and asymptotic growth!

Throughtout his career, I think what made his things special is that he embodies the truest mathematician spirit, which is also the truest geek spirit: starting out with something simple, and then nerding out about it until you have built a whole universe.

Whether it is a place where guns shoot spaceships at 3/8 the speed of light, an algebraic field so vast it includes all other ordered fields and also all infinities, or a concept of numbers atomically decaying, he was a master at whipping out mathematicially consistent fictional worlds.

Goodbye John H. Conway, you were taken from us too soon.